The world population explosion: causes, backgrounds and -projections for the future.

Van Bavel J - Facts Views Vis Obgyn (2013)

Bottom Line:
Next, the mechanisms behind unprecedented population growth are explained and plausible scenarios for future developments are discussed.But in all scenarios, world population will continue to grow for some time due to population momentum.Finally, the paper outlines the debate about the consequences of the population explosion, involving poverty and food security, the impact on the natural environment, and migration flows.

Affiliation: Centre for Sociological Research / Family & Population Studies (FaPOS), Faculty of Social Sciences, University of Leuven, Parkstraat 45 bus 3601, 3000 Leuven, Belgium.

ABSTRACT

Unlabelled: At the beginning of the nineteenth century, the total world population crossed the threshold of 1 billion people for the first time in the history of the homo sapiens sapiens. Since then, growth rates have been increasing -exponentially, reaching staggeringly high peaks in the 20th century and slowing down a bit thereafter. Total world population reached 7 billion just after 2010 and is expected to count 9 billion by 2045. This paper first charts the differences in population growth between the world regions. Next, the mechanisms behind unprecedented population growth are explained and plausible scenarios for future developments are discussed. Crucial for the long term trend will be the rate of decline of the number of births per woman, called total fertility. Improvements in education, reproductive health and child survival will be needed to speed up the decline of total fertility, particularly in Africa. But in all scenarios, world population will continue to grow for some time due to population momentum. Finally, the paper outlines the debate about the consequences of the population explosion, involving poverty and food security, the impact on the natural environment, and migration flows.

Key words: Fertility, family planning, world population, population growth, demographic transition, urbanization, population momentum, population projections.

Mentions:
The power and direction of population momentum is dependent on the age structure of the population. Compare the population pyramids of Egypt and Germany (Fig. 7). The one for Egypt has a pyramidal shape indeed, but the one for Germany looks more like an onion. As a consequence of high birth rates in the previous decades, the largest groups of Egyptians are to be found below the age of forty; the younger, the more voluminous the generation. Even if the current and future generations of Egyptians would limit their fertility strongly (as is indeed the case), the birth rate in Egypt would still continue to rise for quite some time, just because year after year more and more potential mothers and fathers reach the fertile ages. Egypt therefore clearly has a growth momentum.

Mentions:
The power and direction of population momentum is dependent on the age structure of the population. Compare the population pyramids of Egypt and Germany (Fig. 7). The one for Egypt has a pyramidal shape indeed, but the one for Germany looks more like an onion. As a consequence of high birth rates in the previous decades, the largest groups of Egyptians are to be found below the age of forty; the younger, the more voluminous the generation. Even if the current and future generations of Egyptians would limit their fertility strongly (as is indeed the case), the birth rate in Egypt would still continue to rise for quite some time, just because year after year more and more potential mothers and fathers reach the fertile ages. Egypt therefore clearly has a growth momentum.

Bottom Line:
Next, the mechanisms behind unprecedented population growth are explained and plausible scenarios for future developments are discussed.But in all scenarios, world population will continue to grow for some time due to population momentum.Finally, the paper outlines the debate about the consequences of the population explosion, involving poverty and food security, the impact on the natural environment, and migration flows.

Affiliation:
Centre for Sociological Research / Family & Population Studies (FaPOS), Faculty of Social Sciences, University of Leuven, Parkstraat 45 bus 3601, 3000 Leuven, Belgium.

ABSTRACT

Unlabelled: At the beginning of the nineteenth century, the total world population crossed the threshold of 1 billion people for the first time in the history of the homo sapiens sapiens. Since then, growth rates have been increasing -exponentially, reaching staggeringly high peaks in the 20th century and slowing down a bit thereafter. Total world population reached 7 billion just after 2010 and is expected to count 9 billion by 2045. This paper first charts the differences in population growth between the world regions. Next, the mechanisms behind unprecedented population growth are explained and plausible scenarios for future developments are discussed. Crucial for the long term trend will be the rate of decline of the number of births per woman, called total fertility. Improvements in education, reproductive health and child survival will be needed to speed up the decline of total fertility, particularly in Africa. But in all scenarios, world population will continue to grow for some time due to population momentum. Finally, the paper outlines the debate about the consequences of the population explosion, involving poverty and food security, the impact on the natural environment, and migration flows.

Key words: Fertility, family planning, world population, population growth, demographic transition, urbanization, population momentum, population projections.